Are raw milk, seed oils, uncured deli meat and more good for you?

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When it comes to eating well, making good choices has probably never been quite as confusing as it is right now. “It’s a Wild West out there in terms of health misinformation,” says Walter Willett, a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health. “Anybody can claim to be a nutrition expert, but they are not always reliable sources.”

That’s why it’s important to cast a critical eye on any nutritional information you see online or on social media. “Be especially wary of people who paint foods as 100 percent good or bad or who like to label certain foods as ‘toxic,’” says Jessica Clifford, an extension nutrition specialist in the food science and human nutrition department at Colorado State University. “The truth is rarely that black-and-white.”

Some nutrition topics generate more confusion than others. We asked a few experts to weigh in on five frequently misunderstood issues.

Raw milk

Raw milk — milk that hasn’t been pasteurized — has been in the news a lot lately. Those in favor of it claim that it contains more nutrients and beneficial bacteria than the pasteurized version you get at the grocery store.

Others see it differently. “There’s actually no credible evidence that raw milk is better for you or that pasteurization changes the nutritional quality of milk,” says Alison Kane, a registered dietitian at Massachusetts General Hospital in Boston. “It’s simply a process of heating the milk for a short time to kill off disease-causing organisms” like E. coli, listeria and salmonella.

In fact, many experts say that pasteurization is one of the greatest developments in food safety. And a recent study conducted by the Food and Drug Administration found that pasteurization effectively killed the bird flu virus in all of the milk samples it tested. Also important to know: The bacteria that may be present in raw milk can be dangerous to anyone. But older adults are at a high risk of illness from consuming contaminated food, including raw milk.

Seed oils

These oils — which include canola, grape seed, sunflower and soy — are extracted from the seeds of plants. Critics say that their high levels of omega-6 fats raise inflammation in the body and that consuming them can lead to cancer, heart disease, Type 2 diabetes and other illnesses.

But the scientific evidence doesn’t support that. “In dozens of studies looking at omega-6s and inflammation, I haven’t seen one that shows an inflammatory effect, and roughly half of studies are showing anti-inflammatory effects,” Willett says. For example, a 2019 review of 30 studies, published in the journal Circulation, found that people with the highest blood levels of a type of omega-6 fat called linoleic acid had a 7 percent lower risk of cardiovascular disease, possibly because linoleic acid reduces inflammation. Plus, Willett says, we’ve known for decades that these oils also cut LDL (“bad”) cholesterol levels, and a higher intake of them has contributed significantly to the large decline in deaths from heart disease in the United States.

Another argument that’s made against these oils is that hexane, a solvent used to extract the oil from the seeds, is toxic. “Hexane is a harmful compound,” Clifford says, “but the trace amounts that remain in the oil aren’t likely a concern.”

What may be a legitimate problem with seed oils stems from many of the products they’re found in. “Seed oils are used heavily in a lot of ultra-processed foods,” Clifford says. “But the negative health effects of those foods aren’t from the oils themselves.” Cooking with seed oils or using them in salad dressings isn’t putting your health at risk.

‘No nitrates’ deli meats

The World Health Organization labeled processed meats — such as bacon, hot dogs and deli meats — carcinogenic 10 years ago. And more recent research continues to support that. A 2021 analysis of 148 studies, published in the European Journal of Epidemiology, found that for every 1¾ ounces of processed meat people consume per day, the risk of colon cancer increases by 17 percent.

The culprits are the nitrates used to cure, or preserve, the meats. They interact with protein in meat to form potentially cancer-causing compounds called nitrosamines.

Given that fact, you’d think that you would be better off buying deli and processed meat products labeled “no nitrates.” But this claim only means that no synthetic nitrates were used.

“Some products use natural forms of nitrates like celery seed, so the package can say ‘no nitrates,’” Clifford says. (These products may also be labeled “uncured.”) “But the body reacts to natural nitrates in the same way as it does to synthetic ones.” And regardless of the kind of nitrates in processed meats, you’re also probably getting a large dose of sodium when you eat them, which hikes heart disease risk.

Green powders

If you believe the hype, those concoctions of pulverized, freeze-dried fruits, vegetables and other ingredients have the power to increase your energy, improve your digestion, boost immunity — and maybe eliminate the need to eat actual fruits and vegetables. “Even though these powders appear packed with nutrients, you’re missing out on the fiber, water content and the synergistic interactions that take place when we eat nutrients in whole foods,” Kane says.

It’s also possible that some of the nutrients are destroyed during processing. And because they’re supplements, manufacturers generally don’t have to prove to the Food and Drug Administration that they’re safe and effective. Then there’s the price: Some cost close to $100 for a month’s supply. You can buy a lot of delicious, filling produce for that.

Nightshade vegetables

Eggplant, peppers, potatoes and tomatoes are members of the nightshade family of plants. They’re unique because they contain small amounts of a compound called solanine. Some people think that solanine can cause or exacerbate inflammatory conditions such as arthritis, irritable bowel disease and lupus and other autoimmune diseases.

Solanine can be poisonous in large amounts, but the levels in nightshade vegetables are very low and its link to inflammation is far from conclusive. And these veggies are packed with a variety of antioxidants, like lycopene, beta-carotene and vitamin C, which fight inflammation. “People should be cautious about ruling out a whole group of vegetables,” Clifford says. “These are all good sources of quite a few beneficial nutrients.”

That said, people can develop sensitivities to any type of food. Some with autoimmune conditions have concluded that nightshade veggies aggravate their symptoms, especially if they’ve eaten a large serving. If that’s your experience, Clifford recommends talking with your doctor or a dietitian about trying an elimination diet, where you stop eating the foods and then reintroduce them one by one to see if you have a reaction.

How to spot nutrition myths

When you’re trying to separate nutrition myths from reality, keep these tips in mind:

Check your sources. If you get your information online or from social media, make sure those sources are credible. Look for experts who have an RD, an MD or a PhD in medicine or nutrition and are affiliated with a hospital, university or reliable agency.

Consider the claim. Messages that sound extreme (“Seed oils are toxic!”) or too good to be true (“Cabbage soup melts five pounds a day!”) are unlikely to be correct.

Go beyond the headlines. If the news is reporting on a study touting the surprising benefit of a specific food or diet (“Pistachios protect your eyesight”), dig a little deeper. Look for info on who funded the study. And realize that some headlines can suggest that the evidence is stronger than it actually is. You can search for the study using Google Scholar or at pubmed.gov.

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